# Quantum gravity and inflation

@article{Alexander2003QuantumGA, title={Quantum gravity and inflation}, author={Stephon H. S. Alexander and Justin Malecki and Lee Smolin}, journal={Physical Review D}, year={2003}, volume={70}, pages={044025} }

Using the Ashtekar-Sen variables of loop quantum gravity, a new class of exact solutions to the equations of quantum cosmology is found for gravity coupled to a scalar field, that corresponds to inflating universes. The scalar field, which has an arbitrary potential, is treated as a time variable, reducing the hamiltonian constraint to a time-dependent Schroedinger equation. When reduced to the homogeneous and isotropic case, this is solved exactly by a set of solutions that extend the Kodama…

## 38 Citations

### Inflationary quantum cosmology: General framework and exact bianchi type I solution

- Physics
- 2004

Using the methods of loop quantum gravity, we derive a framework for describing an inflationary, homogeneous universe in a purely quantum theory. The classical model is formulated in terms of the…

### Finite states in four-dimensional quantum gravity: the isotropic minisuperspace Asktekar–Klein–Gordon model

- Physics
- 2008

In this paper, we construct the generalized Kodama state for the case of a Klein–Gordon scalar field coupled to Ashtekar variables in isotropic minisuperspace by a new method. The criterion for…

### The isotropic minisuperspace Asktekar–Klein–Gordon model.

- Physics
- 2008

In this paper we construct the generalized Kodama state for the case of a Klein–Gordon scalar field coupled to Ashtekar variables in isotropic minisuperspace by a new method. The criterion for…

### Existence of generalized quantum Kodama states. II. The minisuperspace Ashtekar--Klein--Gordon model

- Physics
- 2007

Existence of generalized quantum Kodama states. II. The minisuperspace Ashtekar–Klein–Gordon model. Abstract This is the second in a series of papers outlining an algorithm to consistently construct…

### Finite states in 4 quantized dimensional gravity . The anisotropic minisuperspace

- Mathematics
- 2009

Finite states in 4 quantized dimensional gravity. The anisotropic minisuperspace Ashtekar–Klein–Gordon model (Part I). Abstract In this paper we construct the generalized Kodama state for gravity in…

### Existence of generalized Kodama quantum states. III. A new approach to finite, full quantum gravity

- Physics
- 2007

Existence of generalized Kodama quantum states. III. A new approach to finite, full quantum gravity. Abstract This is the third in a series of papers outlining an algorithm to consistently construct…

### Loop Quantum Cosmology

- PhysicsLiving reviews in relativity
- 2005

Quantum gravity is expected to be necessary in order to understand situations where classical general relativity breaks down. In particular in cosmology one has to deal with initial singularities,…

### An invitation to loop quantum gravity

- Physics
- 2004

We describe the basic assumptions and key results of loop quantum gravity, which is a background independent approach to quantum gravity. The emphasis is on the basic physical principles and how one…

### An Inner Product for 4D Quantum Gravity and the Chern-Simons-Kodama State

- Mathematics
- 2022

We demonstrate that reality conditions for the Ashtekar connection imply a non-trivial measure for the inner product of gravitational states in the polarization where the Ashtekar connection is…

### Loop Quantum Cosmology

- PhysicsLiving reviews in relativity
- 2008

L loop quantum cosmology is an application of loop quantum gravity to homogeneous systems, which removes classical singularities and introduces the main effects of quantum effects into effective classical equations, which allow one to avoid the interpretational problems of quantum theory.

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